//===--- HeaderIncludes.h - Insert/Delete #includes for C++ code--*- C++-*-===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_TOOLING_INCLUSIONS_HEADERINCLUDES_H

#define LLVM_CLANG_TOOLING_INCLUSIONS_HEADERINCLUDES_H

#include "clang/Basic/SourceManager.h"

#include "clang/Tooling/Core/Replacement.h"

#include "clang/Tooling/Inclusions/IncludeStyle.h"

#include "llvm/Support/Path.h"

#include "llvm/Support/Regex.h"

#include <list>

#include <unordered_map>

namespace clang {

namespace tooling {

/// This class manages priorities of C++ #include categories and calculates

/// priorities for headers.

/// FIXME(ioeric): move this class into implementation file when clang-format's

/// include sorting functions are also moved here.

class IncludeCategoryManager {

public:

  IncludeCategoryManager(const IncludeStyle &Style, StringRef FileName);

  /// Returns the priority of the category which \p IncludeName belongs to.

  /// If \p CheckMainHeader is true and \p IncludeName is a main header, returns

  /// 0. Otherwise, returns the priority of the matching category or INT_MAX.

  /// NOTE: this API is not thread-safe!

  int getIncludePriority(StringRef IncludeName, bool CheckMainHeader) const;

  int getSortIncludePriority(StringRef IncludeName, bool CheckMainHeader) const;

private:

  bool isMainHeader(StringRef IncludeName) const;

  const IncludeStyle Style;

  bool IsMainFile;

  std::string FileName;

  SmallVector<llvm::Regex, 4> CategoryRegexs;

};

/// Generates replacements for inserting or deleting #include directives in a

/// file.

class HeaderIncludes {

public:

  HeaderIncludes(llvm::StringRef FileName, llvm::StringRef Code,

                 const IncludeStyle &Style);

  /// Inserts an #include directive of \p Header into the code. If \p IsAngled

  /// is true, \p Header will be quoted with <> in the directive; otherwise, it

  /// will be quoted with "".

  ///

  /// When searching for points to insert new header, this ignores #include's

  /// after the #include block(s) in the beginning of a file to avoid inserting

  /// headers into code sections where new #include's should not be added by

  /// default. These code sections include:

  ///   - raw string literals (containing #include).

  ///   - #if blocks.

  ///   - Special #include's among declarations (e.g. functions).

  ///

  /// Returns a replacement that inserts the new header into a suitable #include

  /// block of the same category. This respects the order of the existing

  /// #includes in the block; if the existing #includes are not already sorted,

  /// this will simply insert the #include in front of the first #include of the

  /// same category in the code that should be sorted after \p IncludeName. If

  /// \p IncludeName already exists (with exactly the same spelling), this

  /// returns None.

  llvm::Optional<tooling::Replacement> insert(llvm::StringRef Header,

                                              bool IsAngled) const;

  /// Removes all existing #includes of \p Header quoted with <> if \p IsAngled

  /// is true or "" if \p IsAngled is false.

  /// This doesn't resolve the header file path; it only deletes #includes with

  /// exactly the same spelling.

  tooling::Replacements remove(llvm::StringRef Header, bool IsAngled) const;

private:

  struct Include {

    Include(StringRef Name, tooling::Range R) : Name(Name), R(R) {}

    // An include header quoted with either <> or "".

    std::string Name;

    // The range of the whole line of include directive including any leading

    // whitespaces and trailing comment.

    tooling::Range R;

  };

  void addExistingInclude(Include IncludeToAdd, unsigned NextLineOffset);

  std::string FileName;

  std::string Code;

  // Map from include name (quotation trimmed) to a list of existing includes

  // (in case there are more than one) with the name in the current file. <x>

  // and "x" will be treated as the same header when deleting #includes.

  // std::list is used for pointers stability (see IncludesByPriority)

  llvm::StringMap<std::list<Include>> ExistingIncludes;

  /// Map from priorities of #include categories to all #includes in the same

  /// category. This is used to find #includes of the same category when

  /// inserting new #includes. #includes in the same categories are sorted in

  /// in the order they appear in the source file.

  /// See comment for "FormatStyle::IncludeCategories" for details about include

  /// priorities.

  std::unordered_map<int, llvm::SmallVector<const Include *, 8>>

      IncludesByPriority;

  int FirstIncludeOffset;

  // All new headers should be inserted after this offset (e.g. after header

  // guards, file comment).

  unsigned MinInsertOffset;

  // Max insertion offset in the original code. For example, we want to avoid

  // inserting new #includes into the actual code section (e.g. after a

  // declaration).

  unsigned MaxInsertOffset;

  IncludeCategoryManager Categories;

  // Record the offset of the end of the last include in each category.

  std::unordered_map<int, int> CategoryEndOffsets;

  // All possible priorities.

  std::set<int> Priorities;

  // Matches a whole #include directive.

  llvm::Regex IncludeRegex;

};

} // namespace tooling

} // namespace clang

#endif // LLVM_CLANG_TOOLING_INCLUSIONS_HEADERINCLUDES_H